People have to talk about something just to keep their voice boxes in working order so they’ll have good voice boxes in case there’s ever anything really meaningful to say.
Are your characters talking too much?
Take a dialogue-driven scene you’ve written, and see if you can convey the same information with a third fewer words. Can a gesture, a look, or an action take the place of some of that chit-chat? What if one of your characters could not talk in the scene—what would you do then?
Ask yourself—what are we really learning from this dialogue? Is it an info dump? An “as-you-know-Bob” shortcut? How much is really necessary?